Culverts, pipes, ditches, and other drainage structures are in wide use for such reasons as preventing soil erosion and controlling runoff. Culverts may be installed across or under roadways to prevent flooding of the roadway or to prevent water damage to the surrounding area. In other locations, culverts may be used to prevent alteration of the landscape by erosion, or shifting of the soil, for example. In some areas, controlling runoff from snowmelt is another issue that may be addressed, in part, by the use of culverts.
In some cases, a culvert may lose its function because it is clogged with debris. Culverts may become obstructed by soil, rocks, sand, intrusion of plant roots, snow, ice, or other debris. The location of some culverts may make them particularly susceptible to blockage. One way to address these problems is to place a covering or grating over the openings of the culvert. However, these coverings may require extensive and frequent cleaning and may still allow smaller objects such as sand, silt, and gravel to enter the culvert. Additionally, coverings and gratings may not prevent plant roots from clogging the culvert. Culverts can be removed and replaced periodically but this may involve high costs and may involve disturbing existing roadways and other structures.